Support Material
GCE Electronics
OCR Advanced GCE in Electronics H065
Unit: F614
This Support Material booklet is designed to accompany the OCR Advanced GCE
specification in Electronics for teaching from September 2008.
Contents
Contents
2
Introduction
3
Scheme of Work
5
Lesson Plan
16
Other forms of Support
18
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GCE Electronics
Introduction
Background
A new structure of assessment for A Level has been introduced, for first teaching from September
2008. Some of the changes include:

The introduction of stretch and challenge (including the new A* grade at A2) – to ensure that
every young person has the opportunity to reach their full potential

The reduction or removal of coursework components for many qualifications – to lessen the
volume of marking for teachers

A reduction in the number of units for many qualifications – to lessen the amount of
assessment for learners

Amendments to the content of specifications – to ensure that content is up-to-date and
relevant.
OCR has produced an overview document, which summarises the changes to Electronics. This
can be found at www.ocr.org.uk, along with the new specification.
In order to help you plan effectively for the implementation of the new specification we have
produced this Scheme of Work and Sample Lesson Plans for Electronics. These Support Materials
are designed for guidance only and play a secondary role to the Specification.
Our Ethos
All our Support Materials were produced ‘by teachers for teachers’ in order to capture real life
current teaching practices and they are based around OCR’s revised specifications. The aim is for
the support materials to inspire teachers and facilitate different ideas and teaching practices.
Each Scheme of Work and set of sample Lesson Plans is provided in:

PDF format – for immediate use

Word format – so that you can use it as a foundation to build upon and amend the content to
suit your teaching style and students’ needs.
The Scheme of Work and sample Lesson plans provide examples of how to teach this unit and the
teaching hours are suggestions only. Some or all of it may be applicable to your teaching.
The Specification is the document on which assessment is based and specifies what content and
skills need to be covered in delivering the course. At all times, therefore, this Support Material
booklet should be read in conjunction with the Specification. If clarification on a particular point is
sought then that clarification should be found in the Specification itself.
GCE Electronics
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A Guided Tour through the Scheme of Work
= Innovative Teaching Idea
All the teaching idea contained in the SOW are innovative, but the icon is used to
Highlight exceptionally innovative ideas.
= Stretch & Challenge Activity
This icon is added at the end of text when there is an explicit opportunity to offer
Stretch and Challenge.
= ICT Opportunity
This icon is used to illustrate when an activity could be taught using ICT
facilities.
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GCE Electronics
Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic
MOSFET Circuits
Topic outline
Suggested teaching and homework
activities
MOSFET as a switch
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= Innovative teaching idea
GCE Electronics
Suggested resources
Points to note


Recap simple n-channel MOSFET
behaviour. VGS low: IDS=0mA,
VGS>threshold: IDS>0mA.
Introduce idea of MOSFET as analogue
switch. Ask students to draw multiplexer
from analogues switches and gates.
Introduce diagram of tristate using
MOSFETs and gates. Get students to
predict behaviour for each possible input
condition by identifying which MOSFET is
on.
Power supply, bulb in holder, MOSFET and
heatsink, breadboard, potentiometer.
Ensure MOSFET has adequate rating for
bulb (e.g. IRF520) and use heatsink.
Introduce idea of voltage follower as current
amplifier with offset of Vthreshold.
Students build simple dimmer switch to
illustrate behaviour. Measure Vin and Vout
with voltmeter.
= Stretch and challenge opportunity
idea
= ICT opportunity
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Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
MOSFET characteristics
Topic
Suggested teaching and homework
activities

Discuss use for ac signals and add resistors
and capacitors. Get students to determine
values of resistors to maximise signal size.
Try out design in circuit simulation at home

Look at behaviour of MOSFET by inspecting
graphs of IDS vs VGS on datasheet and
identify threshold voltage and calculate
transconductance, gm.
Introduce investigation into IDS vs VGS
and get students to take result, plot graph of
and find gm and the threshold voltage.
Get students to find transconductance and
threshold voltages from graphs taken from
datasheets or made up.


= Innovative teaching idea
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MOSFET Circuits
Suggested resources
Points to note


MOSFET (e.g. BS170), voltmeter, ammeter,
breadboard power supply, potentiometer.
Datasheet for MOSFETs with graphs of IDS
vs VGS and IDS vs VDS (e.g. Fairchild
website).
= Stretch and challenge opportunity
idea
Get students to keep their MOSFET or store
them with their name on them so that they
can use their graphs to design circuits
around their MOSFET later.
= ICT opportunity
GCE Electronics
Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic
MOSFET Circuits
Topic outline
Suggested teaching and homework
activities
Suggested resources
The MOSFET amplifier


Circuit simulation software, computer and
data projector. Datasheet for MOSFETs
with graphs of IDS vs VGS (e.g. Fairchild
website).

Computers, circuit simulation software,
datasheets for MOSFETs
Introduce MOSFET amplifier with circuit
Points to note
and get students to predict behaviour as
potentiometer is adjusted, test predictions on
simulation.
 Add capacitor and signal generator to
produce amplifier and look at affect of
biasing on clipping. Discuss ideal bias point.

= Innovative teaching idea
GCE Electronics
Get students to calculate IDS for ideal bias
point, find VGS from graph of IDS vs VGS and
= Stretch and challenge opportunity
idea
= ICT opportunity
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Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
Topic
MOSFET Circuits
Suggested teaching and homework
activities
Suggested resources
Points to note


calculate suitable values for a potential
divider.
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


= Innovative teaching idea
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Discuss using high values of resistance for
potential divider to give high input
impedance.
Get students to calculate IDS for ideal bias
point, find VGS from graph of IDS vs VGS for
MOSFET and calculate suitable values for
potential divider and input capacitor.
Students build amplifier and measure gain
using circuit simulation software. Compare
gain with –gm Rd
Adjust gain by altering Rd and potential
divider [Stretch and challenge]
Homework: design MOSFET amplifier to
given specification.
Introduce MOSFET amplifier with drain bias
MOSFETs, resistors, capacitors,
breadboards, power supplies, signal
generators, oscilloscopes, speakers,
microphones.
= Stretch and challenge opportunity
idea
If students use their MOSFET from earlier
they can compare the actual and theoretical
gain
= ICT opportunity
GCE Electronics
Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
Topic
Suggested teaching and homework
activities



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MOSFET as voltage controlled
resistor
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Test on MOSFETS
= Innovative teaching idea
GCE Electronics
MOSFET Circuits

Suggested resources
Points to note
Give out large graphs of IDS vs VDS. Get
students to identify ohmic region. Students
calculate resistance at various VGS and so
can plot graph of RDS vs VGS
Show voltage controlled potential divider
and look at limit of signal size to keep
MOSFET in ohmic region.
Students build voltage controlled potential
divider and use as volume control with
signal generator input and oscilloscope on
output and find gain vs voltage.


Test students on all aspects of MOSFETs
taught

Get students to measure gain with
oscilloscope and signal generator. Compare
gain with -gm Rd
Adjust gain and re-measure.
Attempt to measure bandwidth of amplifier.
Add microphone and speaker to make audio
amplifier [stretch an challenge]
Discuss advantages of drain bias over
potential divider (and problems)

Data sheets with large graphs of MOSFET
behaviour. Graph paper.
MOSFET, variable power supply, sig gen,
oscilloscope
This practical would also work as an am
modulator for communication theory
Test on MOSFETs
= Stretch and challenge opportunity
idea
= ICT opportunity
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Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic
MOSFET Circuits
Topic outline
Suggested teaching and homework
activities
Memory
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
Memory address, data and
control busses
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Memory cells form D-type flipflops
= Innovative teaching idea
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
Suggested resources
Points to note
Teach idea of digital memory as data
(numbers) stored at addresses (numbers).
Use a table with two columns: address,
data. Get students to find the data at a
particular address and write data to a
particular address. Introduce idea of using
binary data and binary addresses and
repeat activity.
Introduce block diagram for memory module
and relate to earlier activity along with
functions of control bus.
Introduce idea of memory cell a store for
one bit and set problems calculating the
number of cells in a module.


Tables as analogue for memory
If MFA memory boards available these give
some good practical

It is useful to have a memory chip to show
the class
Relate number of data lines and address
lines to structure of memory. Set problems
calculating numbers of address and data
lines from specs in catalogues or writing the
spec from the pinout of memory chips.
Teach function of control lines and get
students to write sequence of events with
signal levels for reading and writing specific
data to specific locations.

Electronic catalogue pages for memory
chips
Outline the difference between volatile and
non-volatile memory. Get students to give
examples of each in everyday objects.

Make sure that students cannot build the
circuit but can store and retrieve data to
your instruction

Operation of the memory cell not only tests
understanding of this topic but also revises
the D-type flip-flop
= Stretch and challenge opportunity
idea
= ICT opportunity
GCE Electronics
Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
Memory cells from capaciitors
Topic
Suggested teaching and homework
activities

Design memory cell around D-type flip-flop
build and operate using switches and LED.

Teach the structure of a memory cell
constructed from a capacitor and MOSFET.
Teach the use of the tristate in use with a
data bus- relate to MOSFET work earlier.
Get students to solve written problems
giving the logic states of each tristate in
order to read data from a particular memory
module.

Multiplexers
Registers and processing
binary words
= Innovative teaching idea
GCE Electronics
MOSFET Circuits

Teach idea of multiplexers. Get students to
design logic from truth-table of multiplexer.
Students build multiplexer (in circuit
simulator) to direct different frequency
square waves to an LED or speaker.

Relate use of multiplexers to combining
memory modules and set problems on
constructing large memories using
multiplexed enable lines

Show use of D-type flip-flop as register
(single address memory).
Look at processing of binary numbers. Get
students to add binary numbers by
arranging in columns and carrying. Try other
problems using logistic functions (e.g. AND,

Suggested resources


Points to note
Binary arithmetic problems sheet.
Four bit binary adder chip, LEDs, resistors,
breadboards, power supplies.
= Stretch and challenge opportunity
idea
= ICT opportunity
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Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
Topic
Suggested teaching and homework
activities

Two’s complement
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
Shift registers and serial
processing
MOSFET Circuits


Suggested resources
OR, XOR etc)
Introduce binary full adder chip and get
students to try out with LEDs at out put and
wires at inputs. Set arithmetic problems for
homework.
Introduce idea of adding by making one
number negative then adding. Show two’s
complement of binary numbers and get
students to practice finding two’s
complement.
Set written binary subtraction problems.
Build subtracting circuit by changing
last lesson circuit with the addition
of 4 NOT gates and pulling Cin high.

Last lessons circuit plus NOT gates.
Design a shift register in a circuit simulator
and observe the behaviour. Get students to
record written description of shift registers
behaviour.
Look at processing words using two input
shift registers and one output with common
clock. Get students to try out various
processes in circuit simulator.

Circuit simulator software
Digital processing test

Test on this sections work, to get students
to consolidate knowledge

Digital processing test
Introduction to servo systems

Introduce open and closed loop systems
using block diagrams. Get students to give

Thermistor, motor, fan, blade,
potentiometer, resistors, comparators,
= Innovative teaching idea
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Points to note
= Stretch and challenge opportunity
idea

Be careful of noise from motor disrupting
power supply rails.
= ICT opportunity
GCE Electronics
Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
Topic
MOSFET Circuits
Suggested teaching and homework
activities


Suggested resources
examples of each.
Talk through central heating as example of
on-off servo control in blocks. Give circuit
diagram of automatic fan with student help
and get students to build circuit.
Get students to design block diagrams and
circuits for other on-off control systems.
MOSFET, diode, capacitor, power supply,
breadboard.
Proportional feedback

Draw timing diagrams for on-off control and
indicate problems of no stable output value.
Introduce proportional feedback with block
diagram of proportional feedback system as
solution. Show timing diagram for position
control system and get students to complete
timing diagrams of position control system.

If a chart recorder or similar is available this
is a good example of position control with
proportional feedback.
Difference amplifiers

Draw and difference amplifier circuit. Get
students to build and test behaviour of
difference amplifier.
Draw and get students to analyze position
control circuit including finding gain of
system. Discuss effect of changing gain.

Resistors, op-amp, power supply
breadboard, potentiometers, voltmeters.

Op-amp, potentiometer, resistor, capacitor,
voltmeters, switch, power supply,
breadboard.

Discuss problem of speed and temperature
control. Introduce ramp generator circuit.
Build and test ramp generator with a variety
of input voltages.
Show block diagram of speed control.

Build speed control circuit and look at

On-amp, potentiometer, resistor, capacitor,

Speed and temperature
control. Ramp generator
Speed control circuit
= Innovative teaching idea
GCE Electronics

= Stretch and challenge opportunity
idea
Points to note

Noise can be reduced with capacitor
soldered across motor contacts.
= ICT opportunity
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Electronics H065: Electronic Control Systems: F614
Suggested
teaching time
Topic outline
Topic
Suggested teaching and homework
activities

Linear power supply
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Switched mode power supply

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Voltage regulator

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Servo systems test
= Innovative teaching idea
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MOSFET Circuits

Suggested resources
various voltages changing.
Students sketch timing diagram for systems
as it responds to changes.
Points to note
voltmeters, switch, motor, MOSFET, power
supply, breadboard.
Show diode bridge and demonstrate with
LEDs to replace diodes on low frequency
signal generator output.
Discuss use of capacitor to smooth output.
Students build unsmoothed supply and
compare input and output on oscilloscope.
Add capacitor and load. Record results.


LED bridge and signal generator.
Sig gen, diodes, resistors and capacitors
oscilloscope.
Introduce block diagram of switched mode
power supply, emphasise element of
feedback. Get students to produce timing
diagram of system.
Show opto-isolator. Students build simple
circuit with opto-isolator to control motor
without causing electrical noise at control
side.

Opto-isolator, switch, resistors, MOSFET,
motor, breadboard, power supplies,
oscilloscope.
Show diagram of voltage regulator and get
students to predict behaviour. Produce
block diagram from circuit diagram and
compare with other control systems.
Get students to build voltage regulator and
plot V out VS Vin.

Power supply, op-amp, resistors,
voltmeters, zener diode, MOSFET,
breadboard.
Test on this sections work to get students to
consolidate knowledge.

Servo systems test
= Stretch and challenge opportunity
idea
= ICT opportunity
GCE Electronics
= Innovative teaching idea
GCE Electronics
= Stretch and challenge opportunity
idea
= ICT opportunity
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Sample GCE Lesson Plan: Electronics H065:
Coursework Module F614
Light Emitting Diodes (F614)
OCR recognises that the teaching of this qualification will vary greatly from school to school and
from teacher to teacher. With that in mind, this lesson plan is offered as a possible approach but
will be subject to modifications by the individual teacher.
Lesson length is assumed to be one hour,
Learning Objectives for the lesson
Objective 1
Students understand and can find the threshold voltage of a MOSFET from a
graph of MOSFET characteristics
Objective 2
Students understand and can calculate the transconductance of a MOSFET
from a graph of MOSFET characteristics
Objective 3
Students can determine the characteristics of a MOSFET experimentally
Recap of previous experience and prior knowledge

Simple model of a MOSFET as a switch and idea of threshold voltage.
Resources Required

Datasheets for a variety of MOSFETs including graphs of IDS vs VGS

Enlarged paper and electronic graphs of IDS vs VGS

Interactive whiteboard

Ammeter

Voltmeter

MOSFET

Graph paper

Power supply

Potentiometer

Breadboard

Wires
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GCE Electronics
Content
Time
Content
5 minutes
Show graph of IDS vs VGS on IWB and get students to identify threshold
voltage. Relate to previous lessons and explain purpose of lesson is to gain
more detailed understanding of behaviour.
5 minutes
Look at shape of graph beyond threshold voltage and get students to see that
behaviour is roughly linear. Calculate slope of graph on IWB and get students
to give units for slope. Introduce term ‘transconductance’ and relate to unit
and use symbol gm.
10 minutes
Give students graphs of IDS vs VGS and get students to find threshold and
transconductance from each graph.
5 minutes
Design experimental set up for circuit with student aid on IWB and ensure
students have pinout for MOSFET.
25 minutes
Students take measurements, plot graph and find threshold and
transconductance for their MOSFET
5 minutes
Compare results with manufacturer’s data sheet. Summarise findings.
10 minutes
Set homework more graphs of IDS vs VGS and get students to find threshold
and transconductance from each graph and get students to sketch graphs
from specifications.
GCE Electronics
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Other forms of Support
In order to help you implement the new Electronics specification effectively, OCR offers a
comprehensive package of support. This includes:
OCR Training
Get Ready…introducing the new specifications
A series of FREE half-day training events are being run during Autumn 2007, to give you an
overview of the new specifications.
Get Started…towards successful delivery of the new specifications
These full-day events will run from Spring 2008 and will look at the new specifications in more
depth, with emphasis on first delivery.
Visit www.ocr.org.uk for more details.
Mill Wharf Training
Additional events are also available through our partner, Mill Wharf Training. It offers a range of
courses on innovative teaching practice and whole-school issues - www.mill-wharf-training.co.uk.
e-Communities
Over 70 e-Communities offer you a fast, dynamic communication channel to make contact with
other subject specialists. Our online mailing list covers a wide range of subjects and enables you to
share knowledge and views via email.
Visit https://community.ocr.org.uk, choose your community and join the discussion!
Interchange
OCR Interchange has been developed to help you to carry out day to day administration functions
online, quickly and easily. The site allows you to register and enter candidates online. In addition,
you can gain immediate a free access to candidate information at you convenience. Sign up at
https://interchange.ocr.org.uk
Published Resources
OCR offers centres a wealth of quality published support with a fantastic choice of ‘Official
Publisher Partner’ and ‘Approved Publication’ resources, all endorsed by OCR for use with OCR
specifications.
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GCE Electronics
Publisher partners
OCR works in close collaboration with three Publisher Partners; Hodder, Heinemann and Oxford
University Press (OUP) to ensure centres have access to:

Better published support, available when you need it, tailored to OCR specifications

Quality resources produced in consultation with OCR subject teams, which are linked to
OCR’s teacher support materials

More resources for specifications with lower candidate entries

Materials that are subject to a thorough quality assurance process to achieve endorsement
Hodder Education is the publisher partner for OCR GCE Electronics
Hodder Education is producing the following resources for OCR GCE Electronics for first teaching
in September 2008, which will be available in Spring 2008.
Brimicombe, M. OCR Electronics for A Level (2008) ISBN: 9780340966358
Approved publications
OCR still endorses other publisher materials, which undergo a thorough quality assurance process
to achieve endorsement. By offering a choice of endorsed materials, centres can be assured of
quality support for all OCR qualifications.
Endorsement
OCR endorses a range of publisher materials to provide quality support for centres delivering its
qualifications. You can be confident that materials branded with OCR’s “Official Publishing Partner”
or “Approved publication” logos have undergone a thorough quality assurance process to achieve
endorsement. All responsibility for the content of the publisher’s materials rests with the publisher.
These endorsements do not mean that the materials are the only suitable resources available or
necessary to achieve an OCR qualification. Any resource lists which are produced by OCR shall
include a range of appropriate texts.
GCE Electronics
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